And there's the key piece of the whole thing:
Be sure you are not navigating to your User library, make sure it's the library that is accessed via Macintosh HD.
In order to remove the Epson folder, you have to go to what is now (in Mavericks) an 'invisible' library. To get to it, rather than your user library, you have to option/click on the Go menu in finder and then select the library that appears in the dropdown. I've been banging my head against the wall for days trying to find an Epson folder in my user library that didn't exist. Till I learned this yesterday, I'd felt a bit like I'd been seeking the grail or some such thing!